This invention relates generally to a transvaginal uterine manipulator. More specifically, it relates to a transvaginal uterine manipulator having an improved tenaculum holder, tip, and handle lever control.
Transvaginal uterine manipulators are medical instruments used to manipulate a patient's uterus during gynecological surgical and diagnostic procedures. Such procedures include dye or radio-opaque liquid injection for fallopian tube patency examination, biopsy tissue collection, and any of numerous open and laparoscopic surgical and diagnostic procedures.
The movement toward laparoscopic gynecologic surgery has generated an awareness and a need for a better uterine manipulator. Previous laparotomy procedures through the abdominal wall provided easy access for traditional manipulation devices. Laparoscopic procedures through small incisions using trocars in the lower pelvic region are constrained by the anatomical boundary conditions such as patient's size, blood vessels, pelvic bones, etc. These boundary conditions restrict the number of trocar ports used in the laparoscopic procedure and their locations. Due to restrictions and cost constraints, the gynecology surgeon will take advantage of the natural operative port--the vagina and uterus. The natural port requires the use of different instrumentation from other laparoscopic tissue manipulators. It requires the use of uterine manipulators with specific features which are not generally found in current instruments available to the gynecologic surgeon. Recent market surveys indicate that nearly all laparoscopic gynecological procedures will utilize a uterine manipulator.
Current uterine manipulators are typified by that described by Valtchev in U.S. Pat. No. 4,022,208. This device allows manipulator movement in one direction only, allows fluid to be dispensed through the tip, and provides a tenaculum holder with a compression spring to apply force to a tenaculum, as well as a cervical sealing surface on the tip. A tenaculum is a forceps instrument which at its distal end is used to grasp the neck of the cervix and by attaching the proximal end of the tenaculum to the manipulator housing, axial force is applied on the tenaculum in the proximal direction to retain the manipulator tip in its position within the uterus. In another Valtchev patent, U.S. Pat. No. 5,100,382, a different means for providing a sealing surface on the tip of the manipulator is described. The interchangeable tip employs the use of an inflatable balloon to provide the requisite sealing.
Other examples of uterine manipulators abound. U.S. Pat. No. 4,089,337 describes a manipulator with an inflatable tip section which is used along with an adjustable spring-loaded disc to seal the cervix. An earlier patent, U.S. Pat. No. 2,482,622, shows many of the features found in uterine manipulator instruments used today, such as: tenaculum holder which is moveable but when in use is rigidly fixed, sealing surface on the manipulator tip, interchangeable tips, and ability to rotate the tip in one direction. The following additional references also describe various uterine manipulators: U.S. Pat. Nos. 4,775,362; 3,877,433; and 3,809,091.
All of the above devices are acceptable and their features are found on instruments used today. However, certain shortcomings are important to overcome. For example, none of these instruments provide a means to apply a constant tensile force on the tenaculum, regardless of the precise positioning of the tenaculum on the tenaculum holder of the manipulator instrument. A constant force on the tenaculum would in turn provide a constant reaction force on the cervix during continued adjustment of the manipulator position. This constant force feature is important in that it provides a constant insertion force on the manipulator tip to retain the tip within the uterus at all times during the procedure and to prevent it from sliding out of position. Additionally, when using the manipulation for liquid injection, the equivalent force provides a reliable hermetic seal between the mouth of the cervix and the cervical sealing surface of the tip. The Valtchev design using a compression spring for this function is subject to the problem of greatly varying force on the tenaculum which depends upon the amount of deflection applied to the compression spring. This results in an uncontrollable and unknown amount of force relied upon to hold the manipulator tip in the uterus. This uncontrollable force may also result in leakage of any medical fluid injected through the manipulator which may be required to determine tubal patency or to deliver medications.
Additionally, none of the current devices provide a direct angular motion relationship between the handle activation lever and the tip movement or an indicator to communicate this relationship to the user. This feature is important to allow the surgeon to know exactly where the tip is positioned at all times even when the manipulator is not visible because it may be located under surgical drapes during the procedure. Some of these devices possess the feature of the handle remaining in a locked position when the surgeon adjusts the handle to the desired position during the procedure, however, the adjustment requires two hands for its accomplishment. The surgeon does not desire the tip position to change relative to the instrument without the surgeon's control.
Accordingly, in the view of the deficiencies of existing uterine; manipulators, what is needed is a uterine manipulator incorporating new features to better serve the gynecological surgeon's needs. Specifically, what is truly desired is a manipulator capable of providing a constant force on the tenaculum regardless of the positioning of the tenaculum in its holder on the manipulator. Additionally, it would be desirable to provide a manipulator where the handle actuation lever can be easily locked into a desired position using only one hand, and that position be clearly indicated as a reliable indication to the surgeon of the corresponding positioning of the tip of the uterine manipulator.